The digital electret microphone is provided with an analog-to-digital conversion on the basis of traditional electret microphone, in order to output the digital electric signal and increase the ability of anti-electromagnetic interference for the microphone and improve the quality of output signal of the microphone. However, being different from the two pin structure of the traditional electret capacitance microphone, the connection terminals of the digital electret capacitance microphone are 4 pin, which respectively are: Power Input End VDD, Clock Input End CLK, Data Output DATA and Ground Terminal GND. In the prior art, the 2 connection pins of the circular patch packaging structure of the traditional electret capacitance microphone adopts the ring structure to make it easy to implement surface mount technology. However, if the 4 pin digital electret capacitance microphone adopts the circular packaging structure either, it is difficult to implement the automatic surface mount technology. So the people skilled in the art has to set the digital electret capacitance microphone as a square packaging structure to make it easier to implement the automatic surface mount technology, which wastes the existed production line of the circular patch packaging and increases enterprise production cost.